<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>边框</title>
    <style>
        .one {
            border: 1px dotted red;
            /*粗细,线性,颜色,写时按这个写*/
            border-width: 1px 20px;
            border-style: dotted solid dashed;
            border-color: red green blue yellow;
            /*把4个边框按照3要素进行拆分,分别设置*/
        }

        .two {
            /*按照4个边框进行设置*/
            border-top: 5px solid blue;
            border-bottom: 5px dotted red;
            border-left: 5px dashed yellow;
            border-right: 5px dashed green;
        }


        .three {
            width: 0px;
            height: 0px;
            border: 50px solid white;
            border-top: 50px solid green;
            border-bottom: none;
        }
        /*边框有三要素:
        粗细,线性,颜色
        只有颜色可以不写,默认是黑色
        剩下的不写,边框无法显示
        */
    </style>
</head>
<body>
<div class="one">
    老骥伏枥
</div>
<div class="two">
    5555555555555555555
</div>
<div class="three">43433443433</div>
</body>
</html>